[gmx-users] CPU running doesn't match command line

[Albert]

Hello:

I submitted two Gromacs GPU MD simulation to the same GPU machine with 
the identical command line:

gmx_mpi mdrun -s 7.tpr -v -g 7.log -c 7.gro -x 7.xtc -ntomp 8 -gpu_id 0 
-pin on >& 7.info
gmx_mpi mdrun -s 7.tpr -v -g 7.log -c 7.gro -x 7.xtc -ntomp 8 -gpu_id 1 
-pin on >& 7.info

In principle, there should be 16 CPU in all  were occupied by these two 
jobs. However, I found that (by command htop) there are only actually 8 
CPU using, although it created 16 thread job..... I am just wondering 
what's happening? If I only submit one job, 8 CPU are occupied.

Thank you very much.

Albert